For migratory birds, a physical barrier upsets the ecosystems on either side that provide food and breeding habitats, while the infrastructure and enforcement along the wall will add noise and light pollution. Those identified as likely to be affected include pygmy owls, hummingbirds, parrots, golden and bald eagles, Mexican quail, wild turkeys, gray hawks, and condors.

The CBD argues that there is overwhelming evidence that the wall will cause more harm than good for the United States.

“The border wall won’t be effective at stopping people seeking a better life from getting to this country, but it will destroy habitat and divide wildlife populations,” Greenwald said. “Building a wall across the entirety of the border would cause massive damage to one of the most biologically diverse regions in North America and would be a boondoggle of the highest order.”